Synthesis of 2,3‐Unsaturated Alkynyl O‐Glucosides from Tri‐O‐acetyl‐D‐glucal by Using Montmorillonite K‐10/Iron(III) Chloride Hexahydrate with Subsequent Copper(I)‐Catalyzed 1,3‐Dipolar Cycloaddition.

Two strategies were considered for the synthesis of 2,3-unsaturated O-glucosyl-1,2,3-triazoles. The first, involving reaction between tri-O-acetyl- d -glucal and triazole alcohols gave no stereoselectivity. A second strategy provided 2,3-unsaturated O-glycosides from glycals and alkynols through a Ferrier rearrangement; this method, employing montmorillonite K-10 doped with iron(III) chloride hexahydrate in dichloromethane afforded new glycosides in good to excellent yields within short times and with high α-stereoselectivities. Subsequently, the glucosides were coupled with 2-azido-1,4-naphthoquinone to produce a new series of 1,2,3-1H-triazolyl O-glucoside derivatives through a click reaction.